Tufting machines

ABSTRACT

In order to provide a ready facility for adjusting the bottom dead-center position of the tufting needles of a tufting machine on needle change or needle-stroke adjustment, the push-rods upon which the needle-bar is mounted are each provided with an extension arm releasably attachable thereto, the arm having a mounting bracket thereon to receive the needle-bar.

a United States Patent [151 3,653,346

Parsons 14 1 Apr. 4, 1972 s41 TUFTING MACHINES 1,697,565 1/1929 Horlacher ..287/l03 R 7 1,988,668 1/1935 Snyder .287/10$ Inventor: Ronald Parsons, Blackburn, England Jackson. 1 R [73] Assignee; Singer Company (U,K Linflted, London 3,361,096 1968 Watkins ..1 12/410 X England 2 970 Primary Examiner-James R. Boler [22] Ffled' 1 1 Attorney-Marshall J. Breen, Chester A. Williams and Julian [21] App1.No.: 79,783 Falk Foreign Application Priority Data [57] ABSTRACT In order to provide a ready facility for adjusting the bottom Oct. 1 l, 1969 Great Britain .,..50,026/69 dead cemer position of the tumng needles of a tumng 52] U S Cl ll2/79R 112/221 287/103 machine on needle change or needle-stroke adjustment, the E D05c /20 6 5 5 /1 4 push-rods upon which the needle-bar is mounted are each pro- 58] Field g 15/ R 79 A 266 410 vided with an extension arm releasably attachable thereto, the

287/52 arm having a mounting bracket thereon to receive the needle- 1 bar.

[56] References Cited 5 Claims, 2 Drawing Figures UNITED STATES PATENTS 2,390,288 12/1945 Ballamy et al. ..112/221 PATENTEDAPR 419 2 3,653 34s SHEET 2 OF 2 FIE-.2.

TUFIING MACHINES The invention concerns tufting machines and has more particular reference to a needle-bar push-rod arrangement.

If it is required to vary the needle-stroke of a tufting machine having an eccentric or cam mechanism for driving the needle-bar it is necessary, in addition to adjusting the stroke, to adjust the position of the push-rod in its housing so as to ensure that the extreme position of the needle-bar at the lower position is the same irrespective of needle-stroke, the adjustment being effected by introducing shims of an appropriate thickness between the needle-bar and push-rod foot, or, in extreme cases, changing to longer or shorter push-rods as appropriate. To follow such a course is a time-consuming and involved procedure and, as such, one which involves an appreciable machine down-time in that an appreciable part of the machine must be stripped down to provide access.

In the case of a tufting machine wherein the bottom deadcenter position of the needle-bar remains constant within the permitted range of adjustment of the needle-stroke, a need to use needles of a different length in order to produce a different fabric will require an adjustment of the push-rod length, with its attendant machine down-time.

The primary object of the present invention is to provide a simple, yet efiective, means for enabling a ready adjustment of the extreme position of the needle-bar, at the lower end of its stroke, to take place.

Thus, according to one aspect of the present invention, there is proposed a needle-bar assembly for a tufting machine which assembly includes a push-rod, an extension arm releasably secured to the push-rod at the remote end thereof a mounting bracket attached to the extension arm likewise at the remote end thereof, and lateral support blocks secured to the said mounting bracket.

According to another aspect of the invention a needle-bar assembly for a tufting machine includes a push-rod, an extension arm releasably secured to the remote end of the push-rod, the said extension arm comprising a rigid elongate member attached to the end of the push-rod in co-axial relationship therewith, and a mounting bracket attached to the said member at the free end thereof.

The invention will now be described further, by way of example only, with reference to the accompanying drawings illustrating one embodiment thereof and in which:

FIG. 1 is a section through a push-rod having an extension according to the invention applied thereto; and

FIG. 2 is a perspective view, partly in section, of the pushrod extension of FIG. 1.

Referring now to the drawings, a push-rod 11 is slidably mounted in a casing 12, the casing 12 being carried in a machine center-beam l3, and an extension 14 is secured to the lower end of the push-rod by a cap-screw 15 extending axially thereof.

A mounting bracket 16, to the opposite sides of which lateral support-blocks 17 are secured, as by welding, is attached to the lower end of the extension, such bracket being releasably attachable to the extension by a clamping screw 18 engaged with a threaded bore 19 in the bracket and receiving a needle-bar 20 at the underside thereof. The needle-bar is attached to the bar by cap-screws 21 extending through the lateral support-blocks 17 to engage screw-threaded holes in the needle-bar, the undersides of the support-blocks 17 being flush with the undersides of the mounting bracket.

The upper end of the extension 14 is stepped, as is clearly apparent in FIG. 1 of the drawings, to engage a complementary formation at the lower end of the push-rod whilst at its lower end, the extension is counterbored to receive the head of screw 15.

If it is required to adjust the effective length of the push-rod consequent upon a change in needle-stroke (or needle length) so as to vary the lowermost position of the needle-bar, this can be achieved quite simply by replacing an extension of a given length with another of a different and more appropriate length. No adjustment additional to that of the replacement of one extension wlth another, save for the inclusion of shims between the upper end of the extension and the lower end of the push-rod, is necessary and all such adjustment as is required can be made without need to strip down the machine.

The invention is not restricted to the exact feature of the embodiment described since alternatives will readily present themselves to one skilied in the art. Thus, for example, whilst the shoulder formed at the upper end of the extension defines an axial flange to engage a counter-bore in the lower end of the push-rod, it may be found preferable to have the upper end of the extension counterbored to receive a complementarily formed lower end of the push-rod.

I claim:

1. In the tufting machine, a needle-bar assembly including a push-rod, an extension-arm releasably secured to the remote end of the push rod, the said extension-arm comprising a rigid elongate member attached to the end of the push-rod in coaxial relationship therewith, said elongate member having an axially directed bore therein, the outer end of said member being counterbored, an attachment screw having a head portion thereon, said head portion being received in said counterbore, and a mounting bracket attached to the said member at the free end thereof.

2. In a tufting machine as claimed in claim 1 wherein that end of the elongate member attached to the push-rod is of stepped configuration.

3. In a tufting machine as claimed in claim 2 wherein said stepped configuration comprises a peripheral step adjacent said end of said elongate member.

4. In a tufting machine as claimed in claim 1 wherein said mounting bracket is releasably attached to said elongate member.

5. In a tufting machine as claimed in claim 1 wherein said mounting bracket includes support blocks secured thereto at opposite sides thereof. 

1. In the tufting machine, a needle-bar assembly including a push-rod, an extension-arm releasably secured to the remote end of the push rod, the said extension-arm comprising a rigid elongate member attached to the end of the push-rod in coaxial relationship therewith, said elongate member having an axially directed bore therein, the outer end of said member being counterbored, an attachment screw having a head portion thereon, said head portion being received in said counterbore, and a mounting bracket attached to the said member at the free end thereof.
 2. In a tufting machine as claimed in claim 1 wherein that end of the elongate member attached to the push-rod is of stepped configuration.
 3. In a tufting machine as claimed in claim 2 wherein said stepped configuration comprises a peripheral step adjacent said end of said elongate member.
 4. In a tufting machine as claimed in claim 1 wherein said mounting bracket is releasably attached to said elongate member.
 5. In a tufting machine as claimed in claim 1 wherein said mounting bracket includes support blocks secured thereto at opposite sides thereof. 